The compounds of the present invention have a novel structure which is characterised by the presence of a cyclopropyl group associated with the aminopyrroline ring. That structure gives them valuable pharmacological properties. In particular, tests have shown them to be capable of inducing a fall in arterial pressure, in cardiac frequency, as well as in disorders of cardiac rhythm. Accordingly, the compounds of the invention are used in the treatment of cardiovascular diseases, especially arterial hypertension, arrhythmia and associated disorders.